Need asap btw its laugage arts

there is no frigate like a book
to take us lands away,
nor any coursers like a page
of prancing poetry--
this traverse may the poorest take
without oppress of toll--
how frugal is the chariot
that bears the human soul

what is the primary metaphor in this poem

(a) the reading experience is compared to taking a journey

(b) a ship is compared to a book

(c) a horse is compared to a page

(d) a chariot is compared to a soul